Parasiticidal preparations



Patented Nov. 14, 1944 UNITED STATES PATENT OFFICE PARASITICIDAL PREPARATIONS William P. ter Horst, Pompton Plains, N. J., as-

signor to United States Rubber Company, New York, N. Y., a corporation of New Jersey No Drawing. Application May 6, 1943,

Serial No. 485,896

Claims. (o1. 167-30) The compound and a method of preparation are described by Zincke in Annalen der Chemie, vol. 328, page 285, (1903).

The 2,3,5,6,6-pentachloro-4-methyl-2,4-cyclohexadienone may be used as a seed protectant and to protect plants or soil from organisms harmful to seeds and plants. It may also be applied to prevent or retard fungus growth and the formation of, for example, mildew on rope, wood, fur, hair, feathers, cotton, wool, leather, rubber, rubberized or synthetic resin-coated fabrics, and the like. The 2,3,5,6,fi-pentachloroi-methyl- 2,4-cyclohexadienone may be applied as dust or sprays or in solution in a suitable solvent. It may be applied diluted or undiluted, or mixed with carrier, or other fungicides or insecticides,

fertilizers, hormones, buffering or safening agents.

The following examples are given to illustrate the invention:

Example I Pea seed, variety Perfection, were tumbled with 1% by weight of the 2,3,5,6,6-pentachloro-4- methyl-2,4-cyclohexadienone in dust form. The seeds were then planted in soil known to be infested with a number of organisms, including Pythium ultimum. The effectiveness of the fungicide was determined by comparing the number of treated seeds which germinated and developed into healthy plants with an equal number of untreated seeds planted under the same conditions. Observations made at the end of ten days showed that 76% of the treated seeds had germinated and grown to healthy seedlings, whereas only 12% of the untreated seeds had germinated. The

seeds and seedlings were observed to be infected with Pythium ultimum which had caused seed and seedling rot, whereas those which were treated with 2,3,5,6,6-pentachloro-4-methyl-2,4-

cyclohexadienone were found to be free of this disease.

Example II The arachnicidal properties of 2,3,5,6,6-penta ch1oro-4-methyl-2, l-cyclohexadienone are shown by the following test;

1 part by weight of 2,3,5,6,6-pentachloro-4-.

methyl-2,4-cyclohexadienone was suspended in 200 parts of water which container part of Nacconal (wetting agent). The dispersion was then sprayed on beam plants heavily infested with red spiders. Counts taken '72 hours after spraying showed that 90% of the spiders had been killed while control plants which had been sprayed with water containing 25% of Nacconal but without the 2,3,5,6,fi-pentachloro-l-methyl- 2,4-cyclohexadienone showed 7% dead.

Example III The repellent properties of 2,3,5,6,6-pentachloro-4-methyl-2,4-cyclohexadienone are shown by the following test:

4 pieces of woolen cloth 1 /2" x 4' were immersed in a 5% solution by weight of the chemical in acetone until saturated with the solution, then removed, air-dried to remove the acetone, and each placed in a separate covered petri dish containing 5 black carpet bettle larvae, and allowed to stand in a dark place at room temperature for three weeks. Four similar pieces of untreated woolen cloth were placed in separate etri dishes, each containing five black carpet beetle larvae and then allowed to stand for three weeks under equal conditions. At the end of this period it was found that very light surface feeding had occurred on the treated samples, whereas very heavy feeding had occurred on the untreated samples.

Having thus described my invention, what I claim and desire to protect by Letters Patent is:

l. A fungicidal composition comprising a carrier and 2,3,5,,6-pentachloro-4-methyl-2A- cyclohexadienone as an essential active ingredient.

2. The method of protecting organic material subject to attack by microorganisms which comprises treatlng said organic material with 2,3,5,6,6-pentachloro-4-methyl 2,4 cyc'lohexa dienone. 1

,3. The method of protecting seeds, plants and soil subject to attack by fungi and insects which comprises treating said material with 2,3,5,6,6- pentachloro-4-methyl-2,4-cyclohexadienone.

4. The method of immunizing seed which comprises treating said seed with 2,3,5,6,6-pentachloro-4-methyl-2,4-cyclohexadienone,

5. The method of controlling mildew on organic material which comprises treating said organic material with 2.3,5,6,6-pentachloro-4-methyl-2,4 cyclohexadienone.

WILLIAM P. TER HORST. 

